99 mercury sable still having egr problems...help!!
crimson_rose82
05-19-2010, 06:16 PM
I have a '99 mercury sable gs. When I went in for my emissions test the egr flow came up as insufficient. I replaced the egr valve as well as the tube that is connected to it and the exhaust manifold (it was rusted really bad). The only problem is my check engine light is still on and blinks when I give the car gas at 30 + mph. Though not as bad after replacing the parts, my car still has a rough idle. Whats up?
Davescort97
05-26-2010, 10:49 PM
Welcome to AF!
Things on the EGR system get carboned up if you make just short trips and fail to change the oil in a timely manner.
Could be the DPFE (differential pressure feedback) sensor needs to be replaced.
There may be a blockage to the throttle body port.
EGR valve may not be opening due to a lack of vacuum.
Solutions:
Clean out the EGR valve, tubing and intake port to remove deposits.
Replace the DPFE sensor.
Check for vacuum at the DPFE.
Things on the EGR system get carboned up if you make just short trips and fail to change the oil in a timely manner.
Could be the DPFE (differential pressure feedback) sensor needs to be replaced.
There may be a blockage to the throttle body port.
EGR valve may not be opening due to a lack of vacuum.
Solutions:
Clean out the EGR valve, tubing and intake port to remove deposits.
Replace the DPFE sensor.
Check for vacuum at the DPFE.
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